top of page

   Tech Tips & Specs


Table  of   Contents 


Master Lock Info - PDFs 


Add Battery
Add Propane
R&M Battery Platform 1408 Displayed
R&M Propane Lock Installed on Trailer Propane Tanks
R&M Jack Back OnTop mounted on Trailer Tongue

    > Add Trailer Battery <

    What You Need to Know

 ▶︎ Wiring batteries in parallel sums amp hour capacities and electrical current limits, but  retains original 12 volt output. 
▶︎ Batteries should be identical - same voltage, capacity, age, brand. Save future grief - buy 2 new, identical, deep cycle batteries. The old one is likely half-shot anyway, and this gives a complete life expectancy reset.
▶︎ Batteries should be the same state of charge. Charge 100% before install.
▶︎ The cable between positive terminals should be same length as between negatives.

▶︎ The gauge of original cables may be big enough for two. Ask your battery vendor. Cables Too Small, BAD!  Too Big, Good! They're inexpensive, don't get cheap now!
▶︎ Use standard color coding for ALL cables - RED positive (+), BLACK negative (-).
▶︎ If connecting more than 2 batteries, check manufacturer for max number that can be paralleled.  Seldom affects just 2 batteries.

How To Do It
▶︎ Mount new battery on trailer, near as possible to old one.
▶︎ Use new RED cable to connect  positive terminals, same length as negative.
▶︎ Use new BLACK cable to connect negative terminals, same length as positive.
▶︎ Connect the original RED, positive  trailer input cable to one battery and the original BLACK, negative trailer input cable  to the other (or last) battery.
▶︎ Repeat to add more paralleled batteries.

    > Add Trailer Propane <

     What You Need to Know   


There are two types of propane tanks: permanent motorhome ASME tanks, and removable DOT tanks, & 3 sizes dominate.
▶︎ 5 gallon 20# hold 4.6 gallons, 17lbs empty, 38lbs full, 36" top-to-ground.
▶︎ 7½ gallon 30# hold 7.0 gallons, 25lbs empty, 55lbs full, 42" top-to-ground.
▶︎ 10  gallon 40# hold 9.4 gallons, 32lbs empty, 72lbs full, 45" top-to-ground.

▶︎ 5 gallon used far more than all others.

▶︎ 7½ gallon are still manageable, used on larger trailers. Usually the best choice.

▶︎ 10 gallon are too heavy & awkward to transport easily, are used commercially & on jumbo RVs, not supported by R&M.

Ways to Expand Propane Capacity
▶︎ Add 2nd 5    gal 4.6 > 9.2       +100%
▶︎ Add 2nd 7½ gal,7.0>14.0       +100%
▶︎ Sub 5 gal, add (1) 7½ 4.6>7.0+  52%

▶︎ Sub 5 gal, add (2) 7½,4.6>14 +204%

▶︎ If adding 2nd 5 gallon, consider (2) 7½.  Small $, triple capacity, still manageable. 
▶︎ Upgrading tank size can usually be done without altering mounting apparatus. except racks may need a longer all-thread rod. 
▶︎ New tank: 5 gallon apprx $60, 7½ $80.


Parts to Plumb 2 Tanks  (new or used)

▶︎ (2) 5 or 7½ gallon propane tanks.

▶︎ Double Propane Tank Rack. 

▶︎ Auto-switch Propane Regulator.

▶︎  (2) Hoses, connect Tanks to Regulator.

How to Do It

▶︎ Bolt rack to tongue (Side Arms?).
▶︎ Bolt regulator to all-thread rod on rack.
▶︎ Mount (2) 5 or 7½ gallon tanks on rack.
▶︎ Connect hoses to regulator, tanks, trailer.
▶︎ Open tank valves, install Propane Lock.

Jack Back Bonus Benefits <

     What You Need to Know

ALL  R&M  Jack Backs:

▶︎ End struggling to hold up your half-opened tailgate with one hand while wrestling heavy objects over it with the other!

▶︎ Make the previously impossible commonplace by creating completely unhindered rear access to stow objects too large, heavy or awkward to lift over a partially-opened tailgate, like dirt bikes, large compressors, generators, storage containers, recreation or sports equipment, etc.

▶︎ Remove the jack from the front of the tongue so you have room to twist & turn large objects as you guide them into the back of your truck or SUV.

▶︎ Create a convenient free area on the tongue to temporarily hold tools, security pins, bars, etc. while hitching and unhitching.

▶︎ Open up space and create clearance to step back and forth over the tongue while hitching to make the process easier, faster and more convenient!

Prod Specs
R&M Jack Back OnSide mounted Facing Out
R&M Company Logo

  Hot-Dip Galvanization <

      What You Need toKnow


▶︎ Hot Dip Galvanization is the ultimate rust prevention technology! Its durability, dependability, uniformity, and effectiveness are unrivalled by any alternative! Consider:

▶︎ When steel is immersed in +830ºF molten zinc, they blend metallurgically. An outer layer of pure zinc is added, and zinc is merged into the steel itself. The zinc is ontop AND inside the steel, and this steel /zinc alloy is denser and stronger than pure steel.

▶︎ Since every part is totally immersed, every nook and cranny is uniformly covered with zinc. Spray-on's can have thin spots, missed spots, hidden crevices and inside surfaces left bare, etc.


▶︎ Galvanization protects on 3 levels: 
1. Barrier Protection: Insulates the steel from air and moisture.
2. Cathodic Protection: The zinc acts as anode and sacrifices itself to             oxidization instead of the steel.
3. Zinc Patina: If damaged, zinc oxidation builds a protective layer that reseals itand maintains protection. And it looks good indefinitely.


▶︎ Galvanizing is impervious to scrapes, scratches or impact damage, so rust can't get a foothold, expand underneath and lift and peel, the great weakness of other methods. And no maintenance is needed.

▶︎ For long-term, continuous exposure, the recommended  temperature is between -40ºF and +392ºF.

▶︎ Galvanization endures for 35 to 50 years in the harshest, salt water environments, 75 to 100 years in typical, in-land locations!.

  > Monocoque Explained <

      What You Need to Know

▶︎ A construction technique that magnifies the strength of its outer surfaces by placing their compressive and tensile forces in direct opposition, so they're capable of serving as the only structural members.
▶︎ Any structure where size and weight are premium can benefit from monocoque design - used in planes and race cars for over a century.
▶︎ Light, stiff, resistant to bending, has more torsional rigidity, and distributes weight more evenly than internal frame.
▶︎ Beneficial because it is light in proportion to size and strength, and its shape can conform to the logic of the component rather than geometry of the internal frame.

   > R&M Product Specs <

   What You Need to Know


R&M                  Setback   Wgt

Model               Min/Max  lbs

OnSide                    Any       6

OnTop                     7-17     21

OnTop Plus             7-21     25

OnTop Maxi            7-37     47

Side-to-Side             8-14     45
Side-to-Side Maxi    8-34     62​

Bat Platform 1408   Any       11

                 Dimensions         •

R&M  Model           Dimensions

OnSide                    9.75 X 10 X 3/16

OnTop                     6.75 X  20 X 2

OnTop Plus             6.75 X  24 X 2

OnTop Maxi            7.5   X  20 X 2

Side-to-Side             9.0   X  24 X 2

STS  Maxi                9.0   X  24 X 2

Bat Platform 1408  14.0    X   8 X 3/16

▶︎ And R&M products are                          Made in the USA!

Sherline Tongue Scale Displayed by R&M
Fastway Flip Foot Displayed by R&M
Cust Svc
Flip Foot
R&M Company Logo

 > An Essential Product <

    R&M Does NOT Sell

Delivers unique benefits to many trailer owners, & merits serious consideration.

▶︎ Sherline™ Trailer Tongue Scales can be the key to avoiding dangerous towing situations. R&M receives NO sales commission, this is objective advice, not an ad. 


▶︎ To properly load and balance a trailer, you must know tongue weight. If known, out-of-spec extremes can usually be corrected by moving fluids and stored items inside. The cost of not knowing could prove much greater, not only in dollars but in grief and hassle!

▶︎ Tongue weight is not a trivial issue for experienced towers. A well-balanced trailer  minimizes stress and fatigue while maximizing comfort and safety. As imbalance increases, handling deteriorates proportionately. On the extremes, too little weight can cause "fishtailing", violent side to side oscillations of the trailer that impair handling and can lead to an out-of-control crash! Too much tongue weight can cause "crabbing", where the tow vehicle's suspension is overloaded, and can also lead to catastrophic instability on the highway!

▶︎ We've used them many times, and found them reliable and effective. All three Sherline™ Scale models are identical except for gauges, Models LM1000, LM2000 and LM5000, specify the maximum tongue weight each gauge can bear, All are same price, under $150.

 ▶︎ Link to vendor's website:

Sherline™ Trailer Tongue Scales 

▶︎ And Sherline™ products are                      Made in thUSA!

>An IndispensibleProduct<

       R&M Does NOT Sell


Delivers unique benefits to many trailer owners, & merits serious consideration.


▶︎ The Fastway Flip™ Jack Foot eliminates a freqiemtly recurring major aggravation for trailer owners. R&M receives NO sales commissions, this is objective advice, not an ad.

▶︎ Trailer jacks must be raised to the max for towing clearance, then lowered to the max for hitching. Whether manual or electric, grinding the jack 50 revolutions twice is an irritating time-waster. Typically, 2 X 4s are used to avoid this, and must be retrieved, stacked, un-stacked and re-stored every time the trailer is setup.

▶︎ Completely automatic, the Flip extends down and locks into place when the jack is extended, then tucks up under the trailer frame when towing. It easily removes for low clearance situations, and fits virtually every trailer: horse, travel, cargo, RV, ATV, and flat bed.

▶︎ The Flip installs in seconds, with no tools for most applications, and fits nearly every 2-1/4" tongue jack- round or square. Comes in two sizes, 4" & 6".

Price: Under $40.

▶︎ Link to vendor's website:

Fastway Flip™ Jack Foot

▶︎ And Fastway™ products are                               Made in the USA!

R&M Customer Service<      What You Need toKnow


▶︎ R&M  provides free technical support for model selection, installations or problems via email, text or phone.

▶︎ If you have unique requirements or a challenging tongue configuration, contact R&M .

▶︎ R&M ,s flexible, modular design allows us to create custom solutions with standard parts with standard prices. There are few trailer tongue mounting requests that ​R&M  cannot satisfy!

bottom of page